7-amino-decahydro-quinolines

ABSTRACT

The new 7-amino-decahydro-quinolines are manufactured by hydroxygenating 5-amino-2-( Beta -cyanoethyl)-5-cyclohexen-1-one in a manner which is in itself known. The 5-amino-2-( Beta cyanoethyl)-5-cyclohexen-1-ones used as the starting substances can be obtained by several reactions, which are disclosed by several publications. One reaction is the cyclisation of cyanoethylated aliphatic ketones in the presence of suitable catalysts. The new 7-amino-decahydro-quinolines represent valuable curing agents for epoxide resins and advantageously 0,5 to 1,3 equivalents of nitrogen-bonded active hydrogen atoms of the 7-amino-decahydro-quinolines are used per 1 equivalent of epoxide groups of the polyepoxide compound.

United States Patent [191 Pfleiderer et al. Apr. 1, 1975 [54]7-AMINO-DECAHYDRO-QUINOLINES 3,459,755 8/1969 Mathison et al. 260/288 R[75] Inventors: gg ggg g iigi zbfig zi Primary E.\'aminerDonald G. Dausi Switzerld Assistant ExaminerMary C. Vaughn Attorney, Agent, orFirmVincent .l. Cavalieri [73] Assignee: Ciba-Geigy Corp., Ardsley, NY.22 Filed: Mar. 26, 1973 I 1 ABSTRACT The new7-amino-decahydro-quinolines are manufac- [211 Appl' 345l54 tured byhydroxygenating 5-amin0-2-(B-cyanoethyh- 5-cyclohexen-l-one in a mannerwhich is in itself [30] Foreign Application Priority Data known. The5-amino-2-(B-cyanoethyl)-5-cyclohexen- Apr. 4. 1972 Switzerland 4895/72l-ones used as the starting Substances can be Obtained by severalreactions, which are disclosed by several [52] U.S. Cl 260/288 R, 260/47R, 260/47 EC, publications. One reaction is the cyclisation of cyano-260/260, 260/283 SY, 260/309.5, 260/348 ethylated aliphatic ketones inthe presence of suitable R, 2 0 4 4 2 0 4 55 2 0 4 5 260/690 catalysts.The new 7-amino-decahydro-quinolines rep- [51] Int. Cl C07d 33/52 resentvaluable curing agents for ePOXide resins and [58] Field of Search260/288 R advantageously 0,5 to equivalents of nitrogenbonded activehydrogen atoms of the 7-amino- [56] References Ci d decahydro-quinolinesare used per 1 equivalent of ep- UNITED STATES PATENTS oxide groups ofthe polyepoxide compound. 3 0l5.66l 1/1962 Georgian 2601289 R 4 Claims,N0 Drawings 7-AMlNO-DECAHYDRO-QUINOLINES The present invention relatesto new 7-aminodecahydro-quinolines of the general formula in which Rdenotes hydrogen or an optionally substituted alkyl radical with l to 5C atoms and R denotes methyl or hydrogen.

Preferably, in the formula (1) the radical R represents hydrogen. themethyl group or the y-aminopropyl group: that is to say,7-amino-decahydro-quinoline, 7- amino-4a-methyl-decahydro-quinoline and7-amino- 4a-( y-aminopropyl )-decahydro-quinoline represent threepreferred forms of the invention. The 7-amino-decahydro-quinolines ofthe formula (1) are manufactured, according to the invention, byhydrogenating a 5-amino-2-(B-cyanoethyU-S- eyelohexen-l-one of theformula in which R and R have the above meaning, in a manner which is initself known.

The hydrogenation is preferably carried out in the presence of acatalyst. Raney nickel or Raney cobalt are particularly effective ashydrogenation catalysts. It is also possible to use a cobalt oxidecatalyst on a suitable carrier material, the catalyst being reduced tocobalt metal catalyst in a stream of hydrogen.

Further possible hydrogenation catalysts are catalysts based on platinumand based on palladium, which can be employed as platinum black orpalladium black, as colloidal platinum or palladium, or as platinumoxide or hydroxide or palladium oxide or hydroxide catalysts. Possiblecarriers for such catalysts are the customary materials such asasbestos, pumice, kieselguhr, silica gel. silicic acid, active charcoaland the sulphates, carbonates or oxides of the metals of group 11 toVIII of the periodic system, especially of magnesium, calcium, barium.zinc. aluminium, iron, chromium and zirconium.

Preferably. very finely divided nickel or cobalt (Raney nickel or Raneycobalt) or Raney nickel of low palladium content are used.

The hydrogenation can be carried out according to the methods customaryin the laboratory and in industry. either without the use of pressure,for example in a duck-shaped shaking vessel, or under pressure in anautoclave.

Solvents which can be used in the hydrogenation are 7 the organicsolvents usually employed together with the abovementioned types ofcatalyst, especially alcohols or ethers, such as methanol. ethanol anddioxane.

Catalytic reduction is as a rule carried out by mixing the suspension orsolution of the particular 5-amino-2- (B-cyanoethyl)-5-cyclohexen-l-onewith the catalyst and passing hydrogen gas into the reaction mixture.The hydrogenation can in principle be carried out under atmosphericpressure and at room temperature but elevated pressures of atmospheresand above, and elevated reaction temperatures in the range of 50 to 150Care preferred. The hydrogenation is continued until no further hydrogenis absorbed. After com pletion of the hydrogenation the catalyst isremoved, for example by filtration, and the solvent is distilled off.

The hydrogenation can also be carried out in accordance with other knownmethods, for example by treatment with alkali metals, such as metallicsodium, in alcoholic solution.

Examples of possible starting substances for the process according tothe invention are the following 5-amino-Z-(B-cyanoethyl)-5-cyclohexen-l-ones of the formula (11):5-amino-2-methyl-2-(B-cyanoethyl)-- -cyanoethyl)- 5-cyclohexen-l-one,5-amino-2,2-bis-(B- cyanoethyD-cyanoethyl)-5-cyclohexen-1-one and 5-amino-Z-(B-cyanoethyl)-5-cyclohexen-1-one.

The 5-amino-2-(B-cyanoethyll-5-cyclohexen-l-ones of the formula (11)used as starting substances in each case can be manufactured accordingto various processes depending on the meaning which R has in thisformula. If R denotes an optionally substituted alkyl radical with l to5 C atoms, that is to say, for example, the methyl group or a,B-cyanoethyl group, it is possible to use known processes in whichcyanoethylated aliphatic ketones are cyclised in the presence ofsuitable catalysts. Such processes are described, for example, in thefollowing publications: Zur Cyclisierung cyanathylierter aliphatischerKetone" (On the Cyclisation of Cyanoethylated Aliphatic Ketones") by M.Cherubim and F. A. Dagga, Angew. Chem. 83 (1971) 896 and Behavior ofS-Ketonitriles Under the Conditions of Basic Catalysis" by T. A.Favorskaya et. al., Journal of Organic Chemistry of the USSR (1969),Vol. 5, No. 7,1,165l,166.

The cyanoethylated aliphatic ketones can as a rule be manufactured ingood yields by a direct addition reaction of acrylonitrile with ketonessuch as, for example, acetone or methyl ethyl ketone. Thus, the additionreaction of 2 molecules of acrylonitrile with methyl ethyl ketone leadsto 4-acetyl-4-methyl-pimelonitrile, whilst the addition reaction of 3molecules of acrylonitrile with acetone leads tol,l,l-tris-(B-cyanoethyU-Z- propanone.

The 5-amino-2-(B-cyanoethyl)-5-cyclohexen-l-one used as the startingproduct for the present process according to the invention can bemanufactured by cyclisation of 3,3-bis-(B-cyanoethyl)-pentane-2,4-dionewith simultaneous splitting off of an acetyl group, in the presence ofalkaline catalysts such as, for example, sodium alcoholate.3,3-Bis-(B-cyanoethyl)-pentane-2,4- dione can be manufactured accordingto a known process, in a simple manner, by cyanoethylation ofacetylacetone in the presence of bases. The procedure is described by G.S. Misra and R. S. Asthana in Liebigs Annalen 609 (1957) 240-246.

A special manufacturing process for 2,6-dimethyl-3-amino-6-(B-cyanoethyl)-cyclohexen-2-one is described in GermanAuslegeschrift No. 2,010,124. Diethyl ketone is reacted withacrylonitrile in a tertiary alcohol and in the presence of aqueousalkali metal hydroxide or alkali metal alcoholate as the catalyst.

The 7-amino-decahydro-quinolines of the formula (I), according to theinvention, represent valuable curing agents for epoxide resins.

Hence, the invention also relates to curable mixtures which are suitablefor the manufacture of mouldings; impregnations, coatings and adhesivebonds and which are characterisedin that they contain (a) a polyepoxidecompound with an average of more than one epoxide group in the molecule,and (b) as the curing agent, a 7-amino-decahydro-quinoline of theformula (I).

Appropriately, 0.5 to 1.3 equivalents, preferably approx. 1.0equivalent, of nitrogen-bonded active hydrogen atoms of7-amino-decahydro-quinoline of the 'formula (I) are used per 1equivalent ofepoxide groups of the polyepoxide compound (a).

Possible polyepoxide compounds (4) are above all those with an averageof more than one glycidyl group, B-methylglycidyl group or2,3-epoxycyclopentyl group bonded to a hetero-atom (for example sulphurand preferably oxygen or nitrogen); in particular, there may bementioned bis-(2,3-epoxycyclopentyl)-ether; diglycidylethers andpolyglycidyl-ethers of polyhydric aliphatic alcohols, such as1,4-butanediol, or polyalkylene glycols, such as polypropylene glycols;diglycidylethers or polyglycidyl-ethers of cycloaliphatic polyols suchas 2,2-bis-(4-hydroxycyclohexyl)-propane; diglycidyl-ethers orpolyglycidyl-ethers of polyhydric phenols, such as resorcinolbis-(phydroxyphenyl)methane, 2,2-bis(p-hydroxyphenyl)- propanediomethane), 2,2-bis(4'-hydroxy-3,5'- dibromophenyl)propane, 1,1,2,2-tetrakis-(phydroxylphenyl)-ethane or of condensation products,obtained under acid conditions, of phenols with formaldehyde, such asphenol novolacs and cresol novolacs; diandpoly-(B-methylglycidyl)-ethers of the abovementioned polyhydric alcoholsor polyhydric phenols; polyglycidyl esters of polybasic carboxylicacids, such as phthalic acid, terephthalic acid, N-tetrahydrophthalicacid and hexahydrophthalic acid; N-glycidyl derivatives of amines.amides and heterocyclic nitrogen bases, such as N,N-diglycidylaniline,N,N-diglycidyltoluidine and N,N,N,N'-tetraglycidyl-bis(paminophenyl)-methane; triglycidyl-isocyanurate; N,N- diglycidylethyleneurea;N,N-diglycidyl-5,5- dimethylhydantoin and N,N'-diglycidyl-5-isopropylhydantoin; N,N-diglycidy1-5,5-dimethyl-6-isopropyl-S,o-dihydro-uracil.

If desired, active diluents such as, for example, styrene oxide,butyl-glycidyl-ether, isooctyl-glycidylether, phenyl-glycidyl-ether,cresyl-glycidyl-ether and glycidyl esters of synthetic highly branchedmainly tertiary aliphatic monocarboxylic acids (CARDURA E) can be addedto the polyepoxides to lower the viscosity.

The curing of the curable mixtures according to the invention to givemouldings and the like is appropriately carried out in the temperaturerange of to 160C. The curing can also be carried out in two or morestages in a known manner, with the first curing stage being carried outat a lower temperature and the post-curing at a higher temperature.

If desired, the curing can also be carried out in two stages by firstprematurely stopping the curing reaction or carrying out the first stageat room temperature or only slightly elevated temperature, whereby acurable pre-condensate which is still fusible and soluble (a socalledB-stage) is obtained from the epoxide component (a) and the amine curingagent (b). Such a precondensate can serve, for example, for themanufacture of pre-pregs, compression moulding compositions or,especially, sintering powders.

In order to shorten the gelling times and/or curing times, it ispossible to add known accelerators for the amine curing reaction, forexample monophenols or polyphenols, such as phenol or diomethane,salicylic acids, tertiary amines or salts of thiocyanic acid, such as NHSCN.

The term curing, as used here, denotes the conversion of the soluble,either liquid or fusible, polyepoxides into solid, insoluble andinfusible, threedimensionally cross-linked products or materials, and inparticular, as a rule, with simultaneous shaping to give mouldings, suchas castings, pressings, laminates and the like or sheet-like structuressuch as coatings, lacquer films or adhesive bonds.

The curable mixtures according to the invention of polyepoxide compounds(a) and 7-amino-decahydroquinolines of the formula (I) as curing agentscan furthermore be mixed, in any stage before curing, with customarymodifiers such as extenders, fillers and reinforcing agents, pigments,dyestuffs, organic solvents, plasticisers, flow control agents, agentsfor controlling thixotropy, flame-proofing substances and mould releaseagents.

As examples of extenders, reinforcing agents, fillers and pigments whichcan be employed in the curable mixtures according to the invention,there may be mentioned: coal tar, bitumen, textile fibres, glass fibres,asbestos fibres, boron fibres, carbon fibres, cellulose, polyethylenepowder and polypropylene powder; quartz powder; mineral silicates, suchas mica, asbestos powder and slate powder; kaolin, aluminium oxidetrihydrate, chalk powder, gypsum, antimony trioxide, bentones, silicaaerogel ("AEROS'IL"), lithopone, baryte, titanium dioxide, carbon black,graphite, oxide pigments, such as iron oxide, or metal powders, suchaluminium powder or iron powder.

Suitable organic solvents for modifying the curable mixtures are, forexample, toluene, xylene, n-propanol. butyl acetate, acetone, methylethyl ketone, diacetonealcohol, ethylene glycol monomethyl ether,monoethyl ether and monobutyl ether.

As plasticisers for modifying the curable mixtures it is possible toemploy, for example, dibutyl phthalate, dioctyl phthalate and dinonylphthalate, tricresyl phosphosphate, trixylenyl phosphate and alsopolypropylene glycols.

As flow control agents when employing the curable mixtures especially insurface protection, it ispossible to add, for example, silicones,cellulose acetobutyrate, polyvinyl butyral, waxes, stearates and thelike (which in part are also used as mould release agents).

Especially for use in the lacquer field, the polyepoxide compounds canfurthermore be partially esterified in a known manner with carboxylicacids, such as, in particular, higher unsaturated fatty acids. It isfurthermore possible to add other curable synthetic resins, for examplephenoplasts or aminoplasts, to such lacquer resin formulations.

The curable mixtures according to the invention can be manufactured inthe usual manner with the aid of known mixing equipment (stirrers,kneaders, rolls and the like).

The curable epoxide resin mixtures according to the invention are aboveall employed in the fields of surface protection. of the electricalindustry and of laminating processes, and in the building industry. Theycan be used, in a formulation suited in each case to the particular enduse, in the unfilled or filled state, if appropriate in the form ofsolutions or emulsions, as paints, lacquers, sintering powders,compression moulding compositions, injection moulding formulations,dipping resins. casting resins, impregnating resins, binders andadhesives, tool resins, laminating resins, sealing compositions andsurface-filling compositions, floor covering compositions and bindersfor mineral, aggregates.

The following epoxide resins were used for the manufacture of curablemixtures, described in the examples: Epoxide Resin A Polyglycidyl-etherresin (technical product) manufactured by condensation of diomethane(2,2-bis(phydroxyphenyl)-propane) with a stoichiometric excess ofepichlorohydrin in the presence of alkali. which is liquid at roomtemperature, consists mainly of diomethane-diglycidylether of theformula and has the following characteristics: Epoxide content: 5.1 5.5epoxide equivalents/kg Viscosity (Hoeppler) at C: 9,000 13,000 cP.Epoxide Resin B Diglycidyl-ethcr resin (technical product) manufacturedby condensation of hydrogenated diomethane (2-.2-bis-(p-hydroxycyclohexyl)-propane) with a stoichiometric excess ofepichlorohydrin in the presence of a1- kali. which is liquid at roomtemperature, consists mainly of hydrogenated diomethane-diglycidyl-etherof the formula and has an epoxide content of 4.46 epoxideequivalents/kg.

. Epoxide Resin C EXAMPLE 1 t a.5-Amino-2-methy1-2-(B-cyanoethyl)-5-cyc1ohexenl-one (M. Cherubim and F.A. Dagga, Angew. Chem. 83. (1971) 896) 0.6 g of sodium is dissolved in120 ml of tert. butanol by boiling for two hours, thereafter 35.6 g of4-acety1- 4-methy1-pime1onitrile (Bruson, Riener, Journ. A.C.S. 64(1942) 2850) are added and the mixture is boiled for 1 /2 hours underreflux. On cooling, crystals separate out from the clear solution andthese are filtered off, washed with isopropanol and dried in vacuo at C.Yield 19.14 g; melting point l54 156C. Concentration of the filtrate ona rotary evaporator and recrystallisation of the residue from 20 ml ofisopropanol yields a further 7.88 g of melting point 150 154C. Totalyield 27.02 g (75.8%).

For analysis, 3.1 g were recrystallised from 20 ml of ethanol. Yield 2.8g, melting point 157-l59C.

Analysis C H N- O (M 178.24) Calculated C 67.3 H 7.91 N 15.71 Found C67.26 H 8.25 N 15.35

The NMR-spectrum in deuterated dimethylsulphoxide proves the structure.

b. 7-Amino-4a-methyl-decahydro-quinoline 172 g of the5-amino-2-methyl-'2-(B-cyanoethyU-S- cyclohexen-l-one (precursor) thusobtained are hydrogenated in 500 ml of ethanol and 150 g of gaseousammonia in an autoclave in the presence of 20 g of Raney nickel at C anda pressure of atmospheres gauge, over the course of 4 hours. Thecatalyst is filtered off and the filtrate is concentrated on a rotaryevaporator. Distillation in vacuo yields 130.4 g of crude amine (80.2%of theory) in which 80% of the main component can be detected by gaschromatography.

For analysis, a small amount was fractionated through a rotating stripcolumn. Boiling point 123C/13 mm Hg.

EXAMPLE 2 7-Amino-decahydro-quinoline 1 14 g of5-amino-2-(B-cyanoethyl)-5-cyclohexenl-one in 350 ml of ethanol and 100g of gaseous ammonia are hydrogenated over the course of 2 hours in anautoclave in the presence of 12 g of Raney nickel at 1 10C and apressure of l atmospheres gauge. After removing the catalyst and thesolvent, the residue is fractionated through a Vigreux column. whereby69.6 g of 7-amino-decahydro-quinoline of boiling point 108-125C at 12 mmHg are obtained. The bulk of the material distils at 117C/l 2 mm Hg. Theamine is solid at room temperature and. as ascertained by a gaschromatogram, consists of at least two of the four possiblestereoisomers.

The substance was analysed as the dipicrate: 150 g of picric acid and500 mg of amine, after twice recrystallising from a mixture of ethanoland a little water, yield 1.19 g of dipicrate of melting point 246248C(decomposition).

7-Amino-4a-(y-aminopropyl)-deeahydro-quinoline 250 g of-amino-2,2-bis-(,B-cyanoethyU-S- eyclohexen-l-one in 850 ml of ethanoland 370 g of gaseous ammonia are hydrogenated over the course of 3 hoursin an autoclave in the presence of 30 g of Rancy nickel at 130C and apressure of 150 atmospheres gauge. The catalyst is removed byfiltration. the filtrate is concentrated on a rotary evaporator and199.6 g of crude amine of boiling point 93193/0.6 mm Hg are isolated bydistillation. For further purification. 147 g of crude amine arefractionated through a packed column. whereby 69.5 g of pure amine ofboiling point 117121/0.07 mm Hg are obtained.

8 at 12 hours at 140 and 6 hours at 160. Testing the material gave thefollowing results: I

The amine according to Manufacturing Example 1 is hence superior to thecommercially availableamines ethylenediamine and isophoronediamine withregard to heat distortion point. As compared to ethylenediamine,

improved flexibility is achieved.

The casting and curing experiment (relating to the amine according toManufacturing Example 1 was repeated, except for the difference thatinstead of the epoxide resin A the epoxide resin B was employed in onecase, and in a further experiment the epoxide resin C was employed. Thetest results are summarised in Table 3.

EXAMPLE 11 The amines of Manufacturing Examples 2 and 3 were employed,in the manner described in Example 1. as

Analysis iL' 25 il 21 1 curing agents for the epoxide resin A. The testdata decllculuml H l termined are listed in Table 3. At the same time,all test Found c 68.46 H 12.01 1N 19.94 40 data from Example 1 were alsoentered in Table 3.

Table 3 HDP. c FS. kg/mm D. mm

Epoxide A B C B C A B C Resin Amine accor ding to 136 12.7 1.3.4

Example 2 Amine accorl ding m' 140 77 147 11.8 7.5 9.2 16.0 7.4 6.0

Example 1 Amine according to 161 10.1 123 Example 3 Ethylenediamine 11763 84 13.4 10.0 15.2 10.8 7.4 3.5

lsophoronediamine 93 9.6 7.1 1 .4 15.8 2.7 4.5

B. Use Examples We claim:

90 1. A 7-amino-decahydro-quinoline of the formula EXAMPLE 1 Tomanufacture a test specimen, the amine according to ManufacturingExample 1 was mixed with the epoxide resin A in the equivalent ratio of1 1 at room temperature. and the mixture was briefly degassed in vacuoand then poured into a mould of size 200 X 200 X 4 mm. Thereafter themixture was cared for 4 hours 3. 7-Amino-4a-( 'y-aminopropyl)-decahydr0- quinoline.

4. 7-Amino-decahydro-quinoline.

1. A 7-AMINO-DECAHYDRO-QUINOLINE OF THE FORMULA 2.7-Amino-4a-methyl-decahydro-quinoline.
 3. 7-Amino-4a-( gamma-aminopropyl)-decahydro-quinoline.
 4. 7-Amino-decahydro-quinoline.